A three-year randomized clinical trial evaluating direct posterior composite restorations placed with three self-etch adhesives

Figures & data

Figure 1. CONSORT Flow diagram.

Table 1. Distribution of cavity class among groups.

Cavity Class	Restorative systems			Sig.
	SBU/FZXT	GB/GP	OBX/HU
Class I (with Buccal, palatal or lingual extension)	3 (6.5%)	3 (6.5%)	1 (2.2%)	0.871 Fisher Exact Test
Class I	11 (23.9%)	12 (26.1%)	12 (26.1%)
Class II OD, OM	21 (45.7%)	20 (43.5%)	20 (43.5%)
Class II MOD	11 (23.9%)	11 (23.9%)	13 (28.3%)
Total	46 (100.0%)	46 (100.0%)	46 (100.0%)

Table 2. Distribution of tooth types among groups.

	Restorative systems			Sig.
Tooth	SBU/FZXT	GB/GP	OBX/HU
Premolar	21 (45.2%)	19 (45.2%)	20 (51.6%)	0.971 Fisher Exact Test
Molar	25 (54.8%)	27 (54.8%)	26 (48.4%)
Total	46 (100.0%)	46 (100.0%)	46 (100.0%)

Table 3. Name, composition, application and batch numbers of used materials.

Adhesive	Composition and pH^a	Application^a	Resin Composite	Composite Composition^a
Scotchbond Universal (3M ESPE, Seefeld, Germany) One-bottle system self- etch Lot 532117	Adhesive MDP Phosphate monomer, Dimethacrylate Resins, HEMA,Vitrebond copolymer, Filler, Ethanol, Water, Intiators, Silane. Ultra-mild (pH≈2.7)	1.Apply scotch bond universal adhesive to prepared tooth. 2. Rub for 20 seconds. 3.Gently air-dry adhesive for 5 seconds to evaporate solvent. 4. Light cure for 10 seconds.	Filtek Z350 Lot 497440	Resin UDMA, Bis-EMA, Bis-GMA, TEGDMA Fillers Silica (20 nm non-agglomerated/aggregated) zirconia (4–11 nm non-agglomerated/aggregated and agglomerated) clusters, zirconia/ silica aggregated particles (20 nm silica particles combined with 4-11 nm zirconia.
G-aenial Bond (GC Corporation, Tokyo, JAPAN) One-bottle system self- etch Lot 1410101	4-META Phosphoric acid ester monomer, Dimethacrylate monomers, Distilled water, Acetone, Silicon dioxide, Photo-initiator Intermediately strong (pH≈1.5)	1.Shake bottle of G-Bond 2. Apply to the enamel and dentin using disposable applicator brushes. 3. Leave undisturbed for 10 seconds after application. 4. Dry thoroughly for 5 Seconds 5.Light cure for 10 seconds.	G-aenial posterior Lot 201204091	Resin UDMA Dimethacrylate co-monomers Fillers milled pre-polymerized fillers averaging 16 to 17μ in size. Fluoroaluminosilicate glass. Fumed silica is dispersed between the pre-polymerized fillers and the other inorganic fillers.
OptiBond XTR (Kavo Kerr; Orange, CA, USA) Two-bottle system Self-etch Lot 4866387 Lot 4866388	Primer: Glycerol diphosphate monomer (GPDM), hydrophilic co-monomers and di-functional methacrylate monomers, water, acetone, ethyl alcohol, camphorquinone (pH≈2.4) Adhesive: hydrophobic cross-linking monomers, ethyl alcohol, camphorquinone, 0.4-μm barium glass 15%, sodium hexafluorosilicate Mild(pH≈3.4)	1. Apply OptiBond XTR Primer to enamel/dentin using scrubbing motion. 2. Air thin with medium pressure. 3. Shake OptiBond XTR adhesive briefly. Apply to enamel/dentin surface using light brushing motion. 4.Air thin with medium air pressure and then strong air for at least 5 seconds. 5. Light cure for 10 seconds. 6. Place composite according to manufacturer’s instructions for use and light cure.	Herculite Ultra Lot 3318302	Resin Uncured Methacrylate Ester Monomers Fillers Three fillers—prepolymerized filler (PPF), silica nanofillers (20 − 50 nm), Barium glass (0.4 micron).

HEMA: Hydroxyethylmethacrylate; MDP: Methacryloyloxydecyl dihydrogen phosphate; TEGDMA: trietyleneglycoldimethacrylate; UDMA: Urethanedimethacrylate; GPDM: Glycerol-phosphate-dimethacrylate; Bis-GMA: Bisphenol A-glycidyl methacrylate; Bis-EMA: Bisphenol A ethoxylate dimethacrylates; 4-META: 4-methacryloxyethyl trimellitate anhydride.

^aAccording to manufacturers’ MSDS (material safety data sheet).

Table 4. Modified US Public Health Service criteria for direct clinical evaluation of restorations.

Criteria	Definition
Anatomical form	A: Restoration is continuous with existing anatomical form. B: Restoration is discontinuous with existing anatomical form but missing material is not sufficient to expose dentin or base. C: sufficient material is lost to expose dentin or base.
Marginal adaptation	A: The explorer does not catch. B: Explorer catches, no crevice is visible in to which explorer will penetrate. C: Obvious crevice at margin, enamel, dentin or base exposed. D: Restoration is mobile, fractured or missing.
Color match	A: Restoration matches the shade and translucency of adjacent tooth structure. B: Perceptible mismatch, but mismatch is within the normal range of tooth shades. C: The mismatch is outside the normal range of tooth shades and translucency.
Marginal discoloration	A: No discoloration anywhere along the margin. B: Superficial staining (removable, usually localized). C: Deep staining (not removable, generalized).
Surface texture	A: No surface roughness or pits. B: Slight surface roughness or pitted surface. C: Obvious surface roughness or pitted surface.
Secondary caries	A: No caries is present. D: Caries is present.

A: Alpha; B: Bravo; C: Charlie; D: Delta.

Table 5. Descriptive statistics of the evaluated parameters for each restorative system.

	SBU/FZXT	GB/GP	OBX/HU	p Value
Anatomical Form
Evaluation period
Baseline	1.02 ± 0.147^4 (n = 46)	1.02 ± 0.147 (n = 46)	1.00 ± 0.000 (n = 46)	.604
6 months	1.07 ± 0.327^4,5 (n = 46)	1.02 ± 0.147 (n = 46)	1.00 ± 0.000 (n = 46)	.360
12 months	1.11 ± 0.379^5,6 (n = 46)	1.07 ± 0.327 (n = 46)	1.00 ± 0.000 (n = 46)	.127
36 months	1.15 ± 0.470^6 (n = 31)	1.04 ± 0.206 (n = 29)	1.04 ± 0.295 (n = 31)	.182
-p-value	0.036	0.801	0.392
Marginal Adaptation
Baseline	1.04 ± 0.206^4 (n = 46)	1.02 ± 0.147 (n = 46)	1.00 ± 0.000 (n = 46)	.362
6 months	1.17 ± 0.437^2/4,5 (n = 46)	1.11 ± 0.482^1,2 (n = 46)	1.00 ± 0.000^1 (n = 46)	.020
12 months	1.30 ± 0.511^3/5,6 (n = 46)	1.17 ± 0.570^2 (n = 46)	1.02 ± 0.147^1 (n = 46)	.001
36 months	1.48 ± 0.752^2/6 (n = 31)	1.09 ± 0.354^1 (n = 29)	1.11 ± 0.482^1 (n = 31)	<.001
-p-value	<0.001	0.156	0.066
Colour Match
Baseline	1.04 ± 0.206 (n = 46)	1.02 ± 0.147^4 (n = 46)	1.09 ± 0.285 (n = 46)	.351
6 months	1.04 ± 0.206 (n = 46)	1.02 ± 0.147^4 (n = 46)	1.09 ± 0.285 (n = 46)	.351
12 months	1.07 ± 0.250 (n = 46)	1.04 ± 0.206^4 (n = 46)	1.09 ± 0.285 (n = 46)	.702
36 months	1.11 ± 0.315 (n = 31)	1.17 ± 0.437^5 (n = 29)	1.09 ± 0.285 (n = 31)	0.592
-p-value	0.066	0.012	–
Marginal discoloration
Baseline	1.00 ± 0.000^4 (n = 46)	1.00 ± 0.000 (n = 46)	1.00 ± 0.000 (n = 46)	1.000
6 months	1.04 ± 0.206^4 (n = 46)	1.02 ± 0.147 (n = 46)	1.00 ± 0.000 (n = 46)	.362
12 months	1.13 ± 0.341^4,5 (n = 46)	1.07 ± 0.250 (n = 46)	1.04 ± 0.206 (n = 46)	.279
36 months	1.26 ± 0.444 ^2/5 (n = 31)	1.07 ± 0.250^1(n = 29)	1.04 ± 0.206^1 (n = 31)	.002
-p-value	<0.001	0.234	0.112
Surface Texture
Baseline	1.04 ± 0.206^4 (n = 46)	1.00 ± 0.000 (n = 46)	1.00 ± 0.000 (n = 46)	.133
6 months	1.13 ± 0.341^2/^5 (n = 46)	1.04 ± 0.206^1 (n = 46)	1.00 ± 0.000^1 (n = 46)	.025
12 months	1.13 ± 0.341^2/5 (n = 46)	1.07 ± 0.250^1,2 (n = 46)	1.00 ± 0.000^1 (n = 46)	.041
36 months	1.13 ± 0.341^2/5 (n = 31)	1.11 ± 0.315^2 (n = 29)	1.00 ± 0.000^1 (n = 31)	.048
-p-value	0.007	0.112	–
Secondary caries
Baseline	1.00 ± 0.000 (n = 46)	1.00 ± 0.000 (n = 46)	1.00 ± 0.000 (n = 46)	1.000
6 months	1.00 ± 0.000 (n = 46)	1.02 ± 0.147 (n = 46)	1.00 ± 0.000 (n = 46)	.368
12 months	1.02 ± 0.147 (n = 46)	1.04 ± 0.206 (n = 46)	1.00 ± 0.000 (n = 46)	.362
36 months	1.04 ± 0.206 (n = 31)	1.07 ± 0.250 (n = 29)	1.00 ± 0.000 (n = 31)	.236
-p-value	0.194	0.172	1.000

1,2,3: Significant difference between the restorative materials (p < .05).

4,5,6: Significant difference in comparison with baseline for each restorative material (p < .05).

n: number of restorations.

Table 6. Failed restorations during the 36 months evaluation, tooth type, year, and reason for failure.

Restorative system	Cavity class/ Tooth	Number of failed restorations	Month(M)	Reasons
Scotchbond Universal	Class II M	1	12 M	Secondary caries
Filtek Z350 XT	Class II M	1	36 M	Marginal fracture
	Class II Pm	1	36 M	Marginal fracture
G-aenial bond	Class II M	1	6 M	Secondary caries
G-aenial Posterior	Class II M	1	12 M	Marginal fracture
	Class II M	1	12 M	Secondary caries
OptiBond XTR	Class II M	1	36 M	Marginal fracture
Herculite Ultra

M: Molar; Pm: Premolars.

Table 7. Number and percentages of restorations for each group evaluated according to the modified USPHS criteria.

SBU/FZXT					GB/GP				OBX/HU
	BL	6 months	12 months	36 months	BL	6 months	12 months	36 months	BL	6 months	12 months	36 months
Anatomical form
A	45 (97.8%)	44 (95.7%)	42 (91.3%)	28 (90.3%)	45 (97.8%)	45 (97.8%)	44 (95.7%)	29 (100.0%)	46 (100%)	46 (100%)	46 (100%)	30 (96.8%)
B	1 (2.2%)	1 (2.2%)	3 (6.5%)	1 (2.2%)	1 (6.5%)	1 (2.2%)	1 (2.2%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)
C	0 (0%)	1 (2.2%)	1 (2.2%)	2 (4.3%)	0 (0%)	0 (0%)	1 (2.2%)	0 (0 %)	0 (0%)	0 (0%)	0 (0%)	1 (3.2%)
Marginal adaptation
A	44 (95.7%)	39 (84.8%)	33 (71.7%)	18 (58.1%)	45 (97.8%)	43 (93.5%)	43 (93.5%)	27 (93.1%)	46 (100%)	46 (100%)	45 (97.8%)	29 (93.5%)
B	2 (4.3%)	6 (13.0%)	12 (26.1%)	11 (35.5%)	1 (2.2%)	2 (4.3%)	1 (2.2%)	1 (3.4%)	0 (0%)	0 (0%)	1 (2.2%)	1 (3.2%)
C	0 (0%)	1 (2.2%)	1 (2.2%)	0 (0%)	0 (0%)	1 (2.2%)	1 (2.2%)	1 (3.4%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)
D	0 (0%)	0 (0%)	0 (0%)	2 (6.5%)	0 (0%)	0 (0%)	1 (2.2%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)	1 (3.2%)
Colour match
A	44 (95.7%)	44 (95.7%)	43 (93.5%)	27 (87.1%)	45 (97.8%)	45 (97.8%)	44 (95.7%)	26 (89.7%)	42 (91.3%)	42 (91.3%)	42 (91.3%)	28 (90.3%)
B	2 (4.3%)	2 (4.3%)	3 (6.5%)	4 (12.9%)	1 (2.2%)	1 (2.2%)	2 (4.3%)	2 (6.9%)	4 (8.7%)	4 (8.7%)	4 (8.7%)	3 (9.7%)
C	0 (0%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)	1 (3.4%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)
Marginal discoloration
A	46 (100%)	44 (95.7%)	40 (87.0%)	22 (71.0%)	46 (100%)	45 (97.8%)	43 (93.5%)	26 (89.7%)	46 (100%)	46 (100%)	44 (95.7%)	30 (96.8%)
B	0 (0%)	2 (4.3%)	6 (13.0%)	9 (29.0%)	0 (0%)	1 (2.2%)	3 (6.5%)	3 (10.3%)	0 (0%)	0 (0%)	2 (4.3%)	1 (3.2%)
Surface texture
A	44 (95.7%)	40 (87.0%)	40 (87.0%)	27 (87.1%)	46 (100%)	44 (95.7%)	43 (93.5%)	26 (89.7%)	46 (100%)	46 (100%)	46 (100%)	31 (100.0%)
B	2 (4.3%)	6 (13.0%)	6 (13.0%)	4 (12.9%)	0 (0%)	2 (4.3%)	3 (6.5%)	3 (10.3%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)
Secondary caries
A	46 (100%)	46 (100%)	45 (97.8%)	30 (96.8%)	46 (100%)	45 (97.8%)	44 (95.7%)	28 (96.6%)	46 (100%)	46 (100%)	46 (100%)	31 (100.0%)
D	0 (0%)	0 (0%)	1 (2.2%)	1 (3.2%)	0 (0%)	1 (2.2%)	2 (4.3%)	1 (2.2%)	0 (0%)	0 (0%)	0 (0%)	0 (0%)

A: Alpha, B: Bravo, C: Charlie, D: Delta, SBU/FZXT: Scotch Bond Universal/Filtek Z350 XT, GB/GP: G- aenial Bond/ G-aenial Posterior, OBX/HU: Opti Bond XTR/Herculite Ultra.

Figure 2. (a) Tooth 15 MOD (SBU/FZXT) preoperative. (b) Tooth 15 MOD (SBU/FZXT) at Baseline. (c) Tooth 15 MOD (SBU/FZXT) at 6 months. (d) Tooth 15 MOD (SBU/FZXT) at 12 months. (e) Tooth 15 MOD (SBU/FZXT) at 36 months.

Figure 3. Tooth 14 OD (SBU/FZXT) superficial marginal discoloration at 36 months.

Figure 4. Tooth 24 OD (GB/GP) Marginal fracture at 6 months.